Finding the cool little parts you like is always a fun challenge. Lately I have seen a shore power inlte I liked, a water inlet I liked, and an instant hot water heater mounted in a 50's Spartan. That I ireally liked, though I don't know how reliable it will be in an Airstream, as the road vibraitons can be hard on eletrical gear.
For the price which is less than half a new Atwood water heater, I may just give it a shot. After all it is way cool looking, and for the limitied hot water we use it will work well. Also we never "boondock" except for a very rare overnighter at a Walmart of truck stop.
Seeing the water and power inlets mounted on a 60s trailer I really liked the clean look, and the modern pieces did not bother me being on a vintage trailer. Originality is fine for some, but I prefer practicality that also looks good.
More wish list items.